Proper docking won't be possible until the docking protocols are known & shared by both the satellites involved. Hijacking a foreign satellite by force presents more challenges and complications.

I heard the Chinese were attempting a similar type of ASAT weapon as you have described - don't know where they got with that.

Given enough resources and tech - I don't see why something like that should be impossible...however I'd think it would be much easier to have a robotic arm extending from your satellite throw the enemy satellite out of orbit.

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Thanks for answering....
Hope we have some kind of weapon against enemy satellites soon.
Those who have already got them are now all clamoring for ban on anymore testing of space weapons.We should have some tests ASAP.

Employees at the Indian Space Research Organisation (Isro) do not open champagne bottles to celebrate success. As soon as a rocket launch is over, they go back to their offices and start working on the next launch. About two years ago, Isro decided that this practice was not good enough. No, they weren’t yearning for the bubbly. Rather, the organisation was keen to begin assembling the next rocket well before a specific launch was over. So, it created teams and processes to that end.

The successful launch of the Geostationary Launch Vehicle (GSLV) Mark III on Monday was a major milestone in Isro’s five-decade history. A similar success would have resulted in celebrations in some space agencies around the world. But, on Tuesday morning, employees at the Satish Dhawan Space Centre (Shar) in Sriharikota were back to working on the half-assembled Polar Satellite Launch Vehicle (PSLV) C-39, which will soon be assembled fully and launched on June 23. “Earlier the entire Shar used to concentrate on one mission,” says director P Kunhikrishnan. “Now we work in parallel to increase the throughput.”

By the end of this month, Isro would have made four rocket launches this year itself. Two of them were technically challenging, one being GSLV Mark III and the other the launch of 104 satellites on one rocket. By the month-end, Isro would also have built four satellites this year. They include the Gsat-19, a sophisticated satellite with high throughput that is expected to improve communication significantly in the country. It was put into orbit on Monday by the GSLV Mark III.

Even a casual observer would have noticed that the frequency of Isro’s missions has been increasing in recent times. Isro is also tackling missions of increasing sophistication, and slowly reducing the gap between India and the other space powers. Early next year, Isro will launch its second lunar mission, consisting of an orbiter, lander and rover.

If the government gives its approval, Isro will also begin work on a human mission sometime soon. With two different rockets and a third to be available soon, Isro will have an increasing presence in the global commercial market. When current chairman Kiran Kumar took over two and a half years ago, Isro was in good shape from a technical perspective.

The Mars mission had been accomplished and the GSLV, a thorn in Isro’s flesh for a long time, had been successfully flown. A cryogenic engine had been developed, and a human crew capsule tested by atmospheric re-entry. Through all these, the PSLV had been launching satellites with exquisite precision.

This was not always the case, as Isro went through a difficult phase about seven years ago. A GSLV launch failed and a cryogenic engine shut off prematurely. Another mission was aborted due to a fuel leak. “When you encounter difficulties,” says Kiran Kumar, “the concentration of the people goes towards solving those problems. But, once these problems are solved, the concentration is on how we can make things happen at a faster pace.”

The technical problems had delayed Isro’s programmes significantly. The GSLV should have been ready by 2009, but its first successful flight was only in 2014. The cryogenic engine should have been ready early in the millennium, but it was successfully flown only in 2014. Even the PSLV had a backlog. The government was aware of the problems, but continued to support the organization.

Soon after he took over, Kumar reengineered Isro to work faster. The senior management sat down and identified the bottlenecks. They strengthened the technical review system. They also optimized procurement and methods of testing. Separate divisions were created to deal with operations and R&D.

Projects were done in parallel. “The chairman asked us to push ourselves to the limit,” says S Somanath, director of the Liquid Propulsion Systems Centre (LPSC) in Thiruvananthapuram. The results were evident soon. The launches increased in frequency.

The backlog of satellites and launches has decreased, but national requirements are so large that Isro will be kept busy for a long time. The commercial opportunities are also not insignificant. “There is a shortage of launchers, whether it is higher capacity of lower capacity,” says Kumar. Isro, especially in the current high-speed environment, has the ability to respond quickly to market needs.

With PSLV launches increasing in frequency, satellite builders get opportunities for launch with low turnaround time. Isro’s launch costs also go down. None of these would have been possible if the technical problems had been left unsolved. In its nine-year history, GSLV Mark I and II together had notched five failures till December 2010. After Mark I failed in December 2010, Isro took two years before trying the next launch. In August 2013, GSLV Mark II flight was aborted due to a fuel leak. These failures delayed GSLV Mark III as well, as its facilities were used for Mark II for some time.

Isro subsequently did such thorough analysis of the GSLV that some of its engineers had said that they would not have known what to do if it had failed again in 2014. Its successful flight in January 2014 was a major turnaround for Isro. The preceding years were the period when Isro engineers mastered several technology areas, including the cryogenic engine, and developed confidence to take more risks. It also grabbed world attention through the mars mission. “Two successful GSLV launches showed that whatever we worked out was successful,” says Kumar. “Technology is no longer an issue.” He could look at more challenging problems from 2015 onwards.

Isro now became very serious about adhering to the fixed launch date. Launch dates became sacrosanct. Only a newly-formed project management council had the right to change a launch date, and that too when done well in advance. Once Isro became serious about not changing the launch date, work culture changed for the better. People picked up speed. “In the aerospace sector, there is a belief that we should not hurry,” says Somanath. “But we can do faster. By doing things faster, nothing bad is going to happen.”

Isro then looked at its testing methods and decided to optimise them. Launch vehicle components were being tested in Thiruvanathapuram, transported to the launch centre at Sriharikota and then tested again. Isro decided to test them only at Sriharikota, thereby saving time. “We took a calculated risk,” says K Sivan, director of the Vikram Sarabhai Space Centre in Thiruvananthapuram.

If the components were found to be faulty during tests at Shar, Isro would have lost more time. However, engineers at VSSC by now have the confidence in their skills to take this risk. The biggest changes were reserved for Shar, which got big investments to create new facilities. Shar also started activities in parallel. It had built a solid stage assembly building, exclusively meant for GSLV Mark III.

This rocket had big solid motors – the third largest in the world – that could not be made by industry, and needed these special facilities for assembly. Isro also decided that the assembly building would be used for PSLV assembly as well. When the solid stage assembly building was being used for multiple vehicles, two vehicles could be assembled in parallel. Earlier the practice was to launch a rocket, clean up and repair the launch pad in about three weeks, and then start the new assembly. Now vehicles are assembled in parallel without affecting each other. Shar is building a third vehicle assembly bay that will be ready by the end of the year, and it will increase the efficiency even more.
Isro has two launch pads. From the first pad, it can launch six PSLVs. When the third assembly bay is ready, the throughput from the second launch pad will increase to ten, or probably 12 when teams are stretched fully. It means that Isro can have 18 launches from next year onwards.

Its launch capacity will remain at this level till it builds a third launch pad. Isro now has an extremely reliable vehicle in PSLV, which is being used by many satellite builders for launch. GSLV Mark II is now operational, and so Isro has a second vehicle for commercial launches. GSLV Mark III will be declared operational after one more flight, scheduled to happen after a year. It can launch satellites of up to 4,000 kg in weight.

As Isro developed more powerful launch vehicles, the weight of communication satellites kept going up. However, electric propulsion in satellites is promising to bring down their weight in the near future. So the GSLV Mark III will enter a lucrative commercial market soon. Big rockets are not optimized to launch 4-5-tonne satellites.

Arianespace, whose Ariane 5 rocket can launch payloads of more than ten tonnes, is now developing Ariane 6 for launching satellites of around five tonnes. So the two GSLV vehicles are addressing a market that may not go away soon. “I am confident that the GSLV Mark III will have a long life,” says K Radhakrishnan, former chairman of Isro.

Over the next few years, Isro is planning to start a joint venture with private industry to launch vehicles and make satellites. Isro itself is going to concentrate on future challenges, leaving the routine jobs to the joint venture. This entity is expected to start work by 2021. Isro’s biggest challenge after that will be to take humans to space.

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Why not they transfer VSSC to Sriharikkotta ??

This transportation of stages to Sriharikota from TVM is time consuming and risky as well .

There was literally a riot at TVM when they started the satellite project (Today's ISAC) in Bangalore, skipping TVM. Also it is nearly impossible to move entire infra & facilities there, as well as the workforce, since Sriharikota is nearly an isolated island kilometers away from any Large city.

There was literally a riot at TVM when they started the satellite project (Today's ISAC) in Bangalore, skipping TVM. Also it is nearly impossible to move entire infra & facilities there, as well as the workforce, since Sriharikota is nearly an isolated island kilometers away from any Large city.

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If not SHAR , then somewhere near SHAR should be selected and a township can be easily developed .

There is no point making a stages and engines 1000km away from launch site and then transporting it by road for every launch.

GSLV Mk III payload to GTO as compared to other rockets is less. (PTI Photo)

CHENNAI: The "Baahubali" or "fat boy" of Indian rockets -- GSLV Mk III -- weighs several tonnes more than some of the other expendable rockets in the world but its carrying capacity is far less, say experts. On June 5, India successfully flight-tested its brand new rocket, the 640 tonne Geosynchronous Satellite Launch Vehicle-Mark III (GSLV Mk III) nick-named "Baahubali" by the Telugu media and "fat boy" by officials of Indian Space Research Organisation (ISRO).

The rocket powered by its own cryogenic engine at the upper stage, placed communication satellite GSAT-19 weighing 3,136 kg or 3.1 tonne.

"The GSLV Mk III rocket weighs 640 tonne with a capacity to carry four tonne satellite. But when one compares the ratio of the GSLV Mk III's weight to its carrying capacity to geo transfer orbit (GTO - where communication satellites will be placed) with rockets of other countries, the former ranks low," an industry expert told IANS on the condition of anonymity.

Sriharikota in Andhra Pradesh is the second best rocket launch site in the world, the expert added.

Agreeing that the GSLV Mk III payload to GTO as compared to other rockets is less, G Ayyappan, Project Director, GSLV Mk III, cited a couple of reasons for it.

"From the rocket's propulsion point of view, in foreign rockets, the lower stages (engines at the lower part of the rocket that are fired first to lift the rocket and make it escape earth's gravitational force) are powered by semi-cryogenic or cryogenic engines," Ayyappan said.

The thrust power of semi-cryogenic or cryogenic engines are higher than that of engines fired with solid fuel.

The GSLV Mk III is a three stage/engine rocket. The core of first stage is fired with solid fuel and its two motors by liquid fuel. The second stage is liquid fuel and the third is the cryogenic engine.

"We use solid fuel in the lower stages as it is cheaper than cryogenic fuel. Even other space agencies are looking to use solid fuel to cut costs," ISRO's Liquid Propulsion Systems Centre Director S. Somanath told IANS.

"But other space agencies are looking at solid fuel to reduce cost only after their rockets carry far much heavier satellites than Indian rockets," the space industry expert pointed out.

ISRO officials said the mass of communication satellites is also coming down and hence India may not need a heavy-lift rocket.

"Nearly 55-60 per cent of a satellite's weight consists of its chemical fuel. Now the idea is to shift to electric propulsion of satellites which would reduce their weight," Ayyappan pointed out.

Somanath said: "ISRO started designing GSLV Mk III with four tonne carrying capacity when it was making two tonne satellites. At the global level also the weight of satellites are coming down. It is very difficult to predict the market trends."

"Electric propulsion will not drastically reduce the weight of satellites to make much of a difference in the rocket's carrying capacity and it cannot replace chemical fuel. The chemical fuel will be used to take the satellite to its space slot and for managing it later electric propulsion would be used," the expert said.

"The Chinese government approved the Long March 5 project sometime mid-2000 to have a rocket with a capacity of 14 tonne. The size of communication satellites will have to go up as there is limitation on the orbital slots. It all boils down to planning and also predicting the global trends," the expert added.

Citing the example of Japanese H-IIB rocket, Ayyappan said the Japanese use lot of composite materials to make the rocket more efficient and light weight.

"In future we will also be using more composites in the upper stages instead of metal. Half of the rocket's velocity is achieved only at the upper stage and composite will be the only choice in future," Ayyappan said.

"The specific impulse of our cryogenic engine is also slightly less than that of others," Somanath added while listing out other reasons for GSLV Mk III's lower carrying capacity.

"The aluminium used in some foreign rockets are less dense and their weight is less. We will also use such materials to reduce the weight of our cryogenic stage by 500-600 kg," he said.

Somanath said there are plans to reduce the weight of the electronics by around 150 kg so that every kilogram of weight reduced increases the payload capacity.

According to him, switching off and restarting of cryogenic stage in the space would also increase the rocket's capacity.

Experts said India has to realise its semi-cryogenic stage faster and it cannot have the luxury of spending a decade or more in developing newer rocket technologies.

"We are planning to realise the semi-cryogenic engine in 2019 and the entire stage by 2021," Somanath said.

Some future enhancements to increase gslv mk3 payload. Its said that gslv mk3 can carry upto 4.5 tonnes with current weakass engines by incorporating various measures as listed above. Also we need to get the SCE asap, involve ukraine , russia whosoever and get it done quickly. Spacex is already getting ahead of us in low cost carrying capablity which is our strength. Their melin 1d engine has T/W of fcuking 200.While we cant compete with that , we atleast need to get SCE to remain competetive.https://www.google.co.in/url?sa=t&r...BQpT8yyXBPb4lXyvA&sig2=jXDoPRDVW6ITvCQVzEbY3w

Some future enhancements to increase gslv mk3 payload. Its said that gslv mk3 can carry upto 4.5 tonnes with current weakass engines by incorporating various measures as listed above. Also we need to get the SCE asap, involve ukraine , russia whosoever and get it done quickly.

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The main reason for the low mass fraction is the large SRBs as mentioned in the article. Actually I'm hoping for better payloads when they reduce the inert mass of C27 stage & increase it's propellent loading to above 30 tonnes. The current inert mass of 5 tonnes is a bit high when compared to equivalent stages like Delta Cryogenic Second Stage & ESC-B.

Everyone seems to blame DRDO and praise ISRO, but does DRDO deserve this blame and ISRO this relative praise. Let's analyze with an open mind, clear vision and perception is most important. The idea is not to reduce achievement of ISRO but to see things in proper light.

The Criterion for success in-case of DRDO is different compared to ISRO. To succeed, Isro has to achieve goals and avoid mistakes. But Isro does not have to compete with international players. DRDO has to achieve goals, avoid mistakes, but it has to compete at international levels.

For example, ISRO has to research and create rockets to launch satellites, make satellites. If ISRO succeeds in placing a satellite in correct orbit and satellite functions properly, it is deemed a success. ISRO's operations are lower in cost due to lower currency exchange rate of India.

In case of DRDO for example, ARJUN MBT has achieved every goal and function of a tank. But does it compare well with other foreign tanks. It is too heavy, too expensive, over sized, even after 30 years of research etc

Let's put Isro through such a comparisons:ISRO 'Fat Boy' GSLV Mk-III Has Very Low Carrying Capacity: Experts
"The GSLV Mk III rocket weighs 640 tonne with a capacity to carry a four-tonne satellite. But when one compares the ratio of the GSLV Mk III's weight to its carrying capacity to geo-transfer orbit (GTO - where communication satellites will be placed) with rockets of other countries, the former ranks low," an industry expert told IANS on the condition of anonymity.

ISRO Mars Orbiter Mission’s Methane Instrument Has a Glitch
Isro has completed the engineering goal of sending a orbiter into correct orbit around Mars. But what about the scientific goals, like using Methane sensor to study Mars atmosphere.

Those who critisize DRDO don't have the idea of the range of the technologies it works. They even didn't have the idea that the DRDO developed the special food processing material to be consumed by the soldiers on the Siachin Glacier, and the technology to grow vegetable of mamoth size in the harsh environment of the Ladakh, whose demand is so much in the local market and making India among the group of 2 nation together with the Norway to have such capability. Those people should see those 1.5 KG onions from the Leh fields.